Tuesday, October 9, 2012

Hate PowerPoint? Here's why you should

I've mentioned Edward Tufte, the statistician and political scientist before. Now I've read Tufte's 2003 essay "The Cognitive Style of PowerPoint: Pitching Out Corrupts Within" which makes a compelling case for ditching PowerPoint in favor of written reports or conversations.

In practice, PP slides are very low resolution compared to paper, most computer screens, and the immense visual capacities of the human eye-brain system. With little information per slide, many slides are needed. Audiences endure a relentless sequentiality . . . Information stacked in time makes it difficult to understand context and evaluate relationships . . . The statistical graphics produced by Power Point are astonishingly thin, nearly content-free.

I could go on, because it's all so well written. One of Tufte's key points is that PowerPoint is designed for the presenter, not for the audience and especially not for the content. He argues that using PowerPoint for presentations means using an underlying metaphor of the software corporation, ie, "a big bureacracy engaged in computer programming (deep hierarchical structures relentlessly sequential, nested, one-short-line-at-a-time)" (the italics are his). A better metaphor, Tufte says, is teaching. Thus the increasing use of PowerPoint in schools is cause for grave concern.

Tufte's examples are many: the most telling is his review of the slides from a presentation by engineers about the space shuttle Columbia's prospects for safe re-entry after foam blocks struck the shuttle during liftoff. He also reproduces Peter Norvig's translation of the Gettysburg Address in PowerPoint (only six slides and worth a look if you haven't already seen it.)

So how do you improve presentations? Tufte says two things: (1) use MS Word, not PowerPoint as your presentation software. (2) Develop a short briefing paper including text, graphics, and sparklines as a handout. The pamphlet is available from Tufte's website here; you can also read a further discussion here.